diff --git a/.dir-locals.el b/.dir-locals.el
index 4cf3418..4207692 100644
--- a/.dir-locals.el
+++ b/.dir-locals.el
@@ -1,4 +1,10 @@
-; emacs config
+; Use with this in your Emacs config:
+;
+; (use-package reformatter)
+; (reformatter-define ormolu-format-0.0.5.0
+;   :program "ormolu-0.0.5.0"
+;   :args '("--ghc-opt" "-XBangPatterns"
+;           "--ghc-opt" "-XTypeApplications"))
 
 ((haskell-mode
    (mode . ormolu-format-0.0.5.0-on-save)))